Glenohumeral deformity in children with internal rotation contractures secondary to brachial plexus birth palsy: intraoperative arthrographic classification.

PURPOSE: To evaluate, with intraoperative arthrography, joint morphology in children undergoing surgical treatment of residual paralysis of the shoulder resulting in brachial plexus birth palsy and to correlate the morphology with the degree of passive external rotation.
MATERIALS AND METHODS: In 64 children (age range, 7 months to 13 years 6 months), an orthopedic surgeon performed intraoperative arthrography and measured passive external rotation while the patient received a general anesthetic. The orthopedic surgeon and three radiologists reviewed arthrograms and in consensus classified glenohumeral joints in one of four categories: concentric, with the humeral head well centered on the glenoid fossa; flat, with flattening of the posterior glenoid; biconcave, with the humeral head in articulation with the posterior of two concavities, which were in the same plane; and pseudoglenoid, with the humeral head in articulation with the more posterior of two concavities, with retroversion and in a plane different from that of the anterior concavity. Kruskal-Wallis test was used to compare preoperative external rotation with four appearances of glenoid.
RESULTS: Twenty-one children had concentric glenohumeral joints; seven children, flat glenohumeral joints; 19 children, biconcave glenoid; and 17 children, pseudoglenoid. Median passive external rotation was -20 degrees for patients with pseudoglenoid, -10 degrees for those with flat or biconcave glenoids, and 0 degrees for those with concentric glenoids. Presence and type of glenoid deformity were significantly associated with severity of internal rotation contracture (P <.001).
CONCLUSION: Consistent patterns of glenohumeral joint deformity in brachial plexus birth palsy were identified and correlated with severity of internal rotation contracture. Copyright RSNA, 2004